• Structural Engineering and Mechanics
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• v.66 no.2
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• pp.273-283
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• 2018

Currently, the dynamic amplification effect of suction is described using the wind vibration coefficient (WVC) of external loads. In other words, it is proposed that the fluctuating characteristics of suction are equivalent to external loads. This is, however, not generally valid. Meanwhile, the effects of the ventilation rate of louver on suction and its WV are considered. To systematically analyze the effects of the ventilation rate of louver on the multi-dimensional WVC of ultra-large cooling towers under suctions, the 210 m ultra-large cooling tower under construction was studied. First, simultaneous rigid pressure measurement wind tunnel tests were executed to obtain the time history of fluctuating wind loads on the external surface and the internal surface of the cooling tower at different ventilation rates (0%, 15%, 30%, and 100%). Based on that, the average values and distributions of fluctuating wind pressures on external and internal surfaces were obtained and compared with each other; a tower/pillar/circular foundation integrated simulation model was developed using the finite element method and complete transient time domain dynamics of external loads and four different suctions of this cooling tower were calculated. Moreover, 1D, 2D, and 3D distributions of WVCs under external loads and suctions at different ventilation rates were obtained and compared with each other. The WVCs of the cooling tower corresponding to four typical response targets (i.e., radial displacement, meridional force, Von Mises stress, and circumferential bending moment) were discussed. Value determination and 2D evaluation of the WVCs of external loads and suctions of this large cooling tower at different ventilation rates were proposed. This study provides references to precise prediction and value determination of WVC of ultra-large cooling towers.

• Journal of Clinical Otolaryngology Head and Neck Surgery
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• v.29 no.2
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• pp.235-239
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• 2018

Due to the structure with one end closed, the external ear resonance effect in which the high frequency is amplified can be generated, and the sound can be perceived well. The external ear resonance normally has a first peak and a second peak. On average, the first peak has a gain of 18.6 dB at 2620 Hz and the second peak has a gain of 18.2 dB at 4210 Hz. The resonance of the external auditory canal changes with the state of the tympanic membrane, the presence of the ventilation tube, and the structure (length, diameter, shape) of the external auditory canal. A patient with a postauricular meatomastoid cutaneous fistula was admitted to the hospital with a foreign body which is the molding of the hearing aid. After removal of the foreign body, the resonance of the external auditory canal was lost and the subjective sound cognitive ability decreased. In the case of postauricular meatomastoid cutaneous fistula, we confirmed the improvement of sound cognitive ability, the change of pure tone hearing threshold, and the change of the external ear resonance after reconstruction of the ear canal without middle ear reconstruction.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.1
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• pp.83-90
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• 2023

The external store fitted to the aircraft may affect the flight characteristics and flight safety of the aircraft, which requires the analyses and testing on it. The purpose of this study is to identify and analyze types of failures that can affect the flight safety of aircraft due to the installation of external stores, and to check the flight safety of aircraft through dropping tests of the external stores. After identifying the types of failures that could affect the flight safety of the aircraft, the criticality was calculated to analyze the effect on the flight safety of the aircraft. Four types of failures were selected: unintentional dropping, failure of dropping, unintentional main wing deployment, and release of tail wing restraint of the external store, which are considered to affect the flight safety of the aircraft due to the operation of the external store. As a result of the aircraft's flight safety analysis on the failure types, the criticality requirements were met. Based on this, after obtaining the airworthiness certification, the drop test was successfully performed to confirm the flight safety of the aircraft by mounting an external store on the aircraft. However, in addition to the four hazards carried out in this study, the real external stores of the military aircraft may have various factors affecting the flight safety of the aircraft, so further research will be needed.

• Journal of Korea Technology Innovation Society
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• v.15 no.2
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• pp.421-442
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• 2012

Many studies have been published on the relationship between project management styles and project performance. In recent researches, it is argued that project management styles should be different based on project characteristics and these project characteristics may have an effect on the relationship between project management styles and project performance. However, there are few empirical studies covering these issues. In this study, we examined the effect of project characteristics (i.e., degree of newness) on the relationship between project management styles (i.e., team autonomy, internal and external communication, individualism orientation) and project performance. The empirical results using 78 government sponsored R&D projects showed that team autonomy has a stronger positive effect on project performance as project newness becomes higher. In addition, as project newness becomes higher, internal communication showed a stronger positive effect on project performance, while external communication had a stronger negative effect.

• Human Ecology Research
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• v.56 no.1
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• pp.85-97
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• 2018

For a further understanding of the Chinese consumer, this study investigated 1) the effects of aesthetic consciousness on make-up attitude, and 2) the differences in the effect of aesthetics consciousness on make-up attitude among age groups. An online survey was conducted on female consumers belonging to the post-80s and 90s generations, living in Xian China. SPSS 24.0 and Amos 18.0 was used for data analysis. Confirmatory factor analysis for the research variables were performed and three factors of aesthetic consciousness (social relations consideration, internal consideration, and external consideration), and four factors of make-up attitude (psychological pleasure, self-satisfaction, consciousness of others, and tool of transformation) were identified. The results from the model test were : 1) aesthetics consciousness was found to vary depending on make-up attitude. Social relations consideration had a positive effects on psychological pleasure, self-satisfaction, and tool of transformation. Internal consideration had a positive effect on self-satisfaction and tool of transformation, and a negative effect on psychological pleasure. External consideration had positive effects on all four factors of make-up attitude. 2) In the post-80s participants, social relations consideration and external consideration had positive effects on all four factors of make-up attitude. Internal consideration s had a negative effect on consciousness of others and a positive effect on tool of transformation. In the post-90s participants, social relations consideration had positive effects on psychological pleasure, self-satisfaction, and tool of transformation. Internal consideration had positive effects on psychological pleasure and self-satisfaction.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.2
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• pp.117-131
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• 2018

This study analyzed the personal characteristics of the SW industry workers and investigated how these individual characteristics affect the satisfaction of job satisfaction. In addition, we examined how satisfaction with these jobs varies according to satisfaction with internal control and external compensation. This study surveyed the employees of SW industry in Seoul and Daegu from September 15 to October 15, 2017. The results of this study are as follows. First, personal characteristics have a significant effect on job satisfaction. Second, extroversion, openness, friendliness and integrity have a significant effect on job satisfaction. This is consistent with the previous study (Park and Song, 2005), which suggests that people with extroversion are more likely to feel positive emotions such as joy. In addition, it is believed that open empathy has a tendency to share with others in work, and positive emotions in work have a significant influence because they show high achievement in work. A friendly person places great importance on a comfortable and harmonious relationship with others, so he builds and maintains good relationships with the members of the organization by trusting others in the organization. Third, nervousness showed no significant effect on job satisfaction. This is consistent with the previous study (Yoo, 1987) in which the more nervousness is, the more unpleasant emotions work and the more negative emotions and negative experiences occur. Fourth, personal characteristics have positive effects on job satisfaction in the moderating effects of intrinsic compensation and external compensation. There is a difference in job satisfaction due to intrinsic compensation and external compensation.

• Journal of Mechanical Science and Technology
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• v.18 no.6
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• pp.990-1001
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• 2004

The retention of a molten pool vessel cooled by internal vessel reflooding and/or external vessel reactor cavity flooding has been considered as one of severe accident management strategies. The present numerical study investigates the effect of both internal and external vessel mixed cooling on an internally heated molten pool. The molten pool is confined in a hemispherical vessel with reference to the thermal behavior of the vessel wall. In this study, our numerical model used a scaled-down reactor vessel of a KSNP (Korea Standard Nuclear Power) reactor design of 1000 MWe (a Pressurized Water Reactor with a large and dry containment). Well-known temperature-dependent boiling heat transfer curves are applied to the internal and external vessel cooling boundaries. Radiative heat transfer has been considered in the case of dry internal vessel boundary condition. Computational results show that the external cooling vessel boundary conditions have better effectiveness than internal vessel cooling in the retention of the melt pool vessel failure.

• Wind and Structures
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• v.11 no.5
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• pp.361-376
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• 2008

This paper considers internal pressure fluctuations for a range of building volumes and dominant wall opening areas. The study recognizes that the air flow in and out of the dominant opening in the envelope generates Helmholtz resonance, which can amplify the internal pressure fluctuations compared to the external pressure, at the opening. Numerical methods were used to estimate fluctuating standard deviation and peak (i.e. design) internal pressures from full-scale measured external pressures. The ratios of standard deviation and peak internal pressures to the external pressures at a dominant windward wall opening of area, AW are presented in terms of the non-dimensional opening size to volume parameter, $S^*=(a_s/\bar{U}_h)^2(A_W^{3/2}/V_{Ie})$ where $a_s$ is the speed of sound, $\bar{U}_h$ is the mean wind speed at the top of the building and $V_{Ie}$ is the effective internal volume. The standard deviation of internal pressure exceeds the external pressures at the opening, for $S^*$ greater than about 0.75, showing increasing amplification with increasing $S^*$. The peak internal pressure can be expected to exceed the peak external pressure at the opening by 10% to 50%, for $S^*$ greater than about 5. A dominant leeward wall opening also produces similar fluctuating internal pressure characteristics.

• Journal of the Korean Society for Railway
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• v.9 no.2 s.33
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• pp.151-159
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• 2006

It analyzed the mechanical behaviors of non-ballasted railway bridge (steel plate girder type) with ballast reinforced on the finite element analysis, field test and laboratory test far the static and dynamic responses. The major objective of this study is to investigate the effects and application of reinforcement for steel plate girder railway bridge by the external post-tensioning method. The reinforcement of non-ballast railway bridge had obviously stable dynamic behaviors due to the additional dead force which was ballast. But in case of static behaviors, static displacements and stresses had increased nearly the allowable values. Therefore we analyzed the mechanical behaviors of non-ballasted railway bridge with ballast reinforced and external post-tensioning reinforced on the finite element analysis and laboratory test for the static and dynamic behavior. As a result, the reinforcement of ballasted railway bridge the external post-tensioning method are obviously effective for the additional dead force which is ballast. The analytical and experimental study are carried out to investigate the post-tension force decrease bending behavior and deflection in composite bridge for serviceability. The servicing railway bridge with ballast reinforced has need of the reasonable reinforcement measures which could be reducing the effect of additional dead load that degradation phenomenon of structure by an unusual. stresses and a drop durability.

• The International Journal of Costume Culture
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• v.12 no.2
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• pp.129-140
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• 2009

In this study, the effect of innovativeness of external networks on the corporate innovativeness and innovation performance were explored based on web survey data collected from 230 manufacturing companies. Specifically, according to the manufacturers' business categories divided by the technology level, three groups such as advance technology (electronic/IT), mid- to high technology (automobile/machine), and low technology (textile/clothing) companies were investigated to find out which external network influences corporate innovativeness and innovation performance. In the result, textile/clothing companies were not different in company size, history, and innovation effort from advanced technology and mid- to high technology companies. Collectively, the innovativeness of external networks affected corporate innovativeness and innovation performance. In the result by a business category, innovativeness and innovation performance of textile/clothing companies were affected by the innovativeness of competitors, whereas automobile/machine companies in the mid- to high technology group were affected by suppliers. In addition, advanced technology (electronics/IT) were affected by buyers and competitors. These differences suggest that the way to use vertical networks toward upstream (e.g., suppliers) and downstream (e. g., buyers) as well as horizontal networks toward competitors can be different by the business category of manufacturers. The result would provide implications for the academia and the industry.